Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0028738 (nystagmus)
 7,431 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of electric stimulation on vestibular compensation was studied in guinea pigs. Pharmacological labyrinthectomy was performed by injecting chloroform into the right middle ear under light ether anesthesia. The guinea pigs were divided into four groups: a control group which was not electrically stimulated after labyrinthectomy, a group stimulated with 0.6 mA square wave, a group stimulated with 0.3 mA square wave, and a group stimulated with 0.6 mA pulse wave. Electric stimulation, which started 1 h and 15 min after labyrinthectomy, was given through retroauricular electrodes. Nystagmus and head deviations were recorded and analyzed to assess the process of compensation at 1, 2, 3, 4, 5, 8, 12, 18 and 24 h after labyrinthectomy. Electrically stimulated groups, especially group 0.6 mA square wave and group 0.6 mA pulse wave, showed faster compensation in nystagmus and head-body deviation than the control group. Therefore, in this study, electric stimulation seemed to contribute favorably to vestibular compensation.
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PMID:Effect of electric stimulation on vestibular compensation in guinea pigs. 175 64

It is known that visual input plays an important part in vestibular compensation. Recent physiological evidence has shown that there are some differences regarding functional contributions to the vestibular nuclei between the right and left eye. The present experiment was undertaken to elucidate the influence of blindfolding one eye on vestibular compensation. Guinea pigs were distributed into three groups: control group, left eye surgically closed, and right eye surgically closed. Chemical labyrinthectomy was performed by injecting chloroform into the left middle ear under light ether anesthesia. Nystagmus beats and head deviations were analysed to assess the process of compensation. Results have shown that the elimination of visual input from one eye ipsilateral to the lesion side could significantly retard the compensation, whereas no significant difference was found between the control eye and the right eye surgically closed group. It is believed that the present result could be due to direction selectivity of visual input in those subjects. The neural mechanism responsible for this result is discussed.
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PMID:Effect of blindfolding one eye on vestibular compensation in guinea pigs. 326 47

The effect of hypergravity on vestibular compensation was studied in guinea pigs. Pharmacological labyrinthectomy was performed by injecting chloroform into the middle ear cavity under ether anesthesia. The guinea pigs were exposed to hypergravity on a centrifuge. The animals were divided into four groups: a group stimulated with 2G after labyrinthectomy of the right ear, a group stimulated with 2G after labyrinthectomy of the left ear to evaluate the influence of the centrifugal rotation, a group stimulated with acceleration and deceleration alone, and a control group which was maintained under similar conditions, but without centrifugation. Head deviation and nystagmus were recorded and analysed to assess the process of compensation at 1, 3, 5, 7 and 9 h after labyrinthectomy. The 2G-stimulated group showed faster compensation in head deviation than the control group. In this study, the hypergravity stimulation seemed to facilitate the compensation in head deviation.
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PMID:Effect of hypergravity on vestibular compensation in guinea pigs. 761 Aug 59

In adult guinea pigs, unilateral labyrinthine lesions were inflicted by chloroform injections into the middle ear. Immunoreactivity for S100 protein (S100) in the vestibular nuclei was studied during compensation of lesion-induced postural asymmetry symptoms, i.e., nystagmus, asymmetrical head position. 1 h after unilateral labyrinthectomy, increased levels of astroglial S100 immunoreactivity were found in the superior vestibular nucleus and in the medial/lateral vestibular nucleus border region on the side contralateral to the deafferentation. Bilaterally, the astrocytic S100 immunoreaction increased in the lateral vestibular nuclei around Deiters neurons. Maximal expression of S100 was noted 3 h after the lesion. Subsequently, it diminished. Our data reveal that transsynaptically altered neuronal activity induces an astrocytic reaction which provides increased levels of S100 to the local neuropil. Calcium and zinc binding S100 proteins may play a functional role for the neuroplasticity during vestibular compensation.
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PMID:Expression of S100 protein in the vestibular nuclei during compensation of unilateral labyrinthectomy symptoms. 854 26